do you know your sweat rate?

As we’ve men­tioned pre­vi­ously in Ultra X Media, one of the most import­ant aspects of race strategy is hydra­tion. It is also some­thing that is often man­aged poorly. This can have a dev­ast­at­ing impact, both on per­form­ance and phys­ic­al con­di­tion.

Stay­ing hydrated does not simply mean drink­ing lots, rather it is prin­cip­ally about main­tain­ing the cor­rect bal­ance of elec­tro­lytes whilst main­tain­ing hydra­tion levels, and this will be dif­fer­ent for every­one.

The stresses placed on the body in an extreme envir­on­ment like Jordan or Sri Lanka mean that most people do con­sider it when plan­ning their race fuel­ing, but it’s not an easy thing to work out.

We are there­fore delighted to announce that for Ultra X Jordan we are team­ing up with Pre­ci­sion Hydra­tion — the Sweat Experts.

This is a key part­ner­ship for us and means that we get to give our cus­tom­ers the best pos­sible oppor­tun­ity to cre­ate the right hydra­tion plan.

All com­pet­it­ors for Ultra X Jordan will be able to bene­fit from a free online Sweat Test to learn about their per­son­al hydra­tion require­ments. They will also have access to an ini­tial plan and a dis­count on Pre­ci­sion Hydra­tion elec­tro­lyte drinks, that match how they sweat.

PH’s products are also going to be avail­able out in Jordan to help you start and stay hydrated dur­ing the event.

The Sweat Test — What and Why?

To many, doing a Sweat Test may seem like an odd step in pre­par­ing for an ultramara­thon.

How­ever, by work­ing out your sweat rate, and import­antly “salt­i­ness”, it is pos­sible to work out 1) how much flu­id you are likely to lose over the course of a race 2) how much salt you lose in that sweat (and as a res­ult how much of both you need to take on board to keep the engine topped up).

One of our founders went for one to find out a bit about the pro­cess.

How it works

Two small elec­trodes are put onto your fore­arm. This stim­u­lates a small patch of skin on your fore­arm to sweat. A sample is then drawn into a watch-like Sweat Col­lect­or and run through a machine to tell you how salty your sweat is. Simple.

The quick­er it fills up, the more you sweat! It takes less than 15 minutes, is done at rest and is non-invas­ive.

Sam’s res­ults

What I expec­ted: My instinct was that I didn’t sweat much and I wasn’t that salty — I tend to per­form well in hot­ter envir­on­ments and whilst I do quite a lot of miles all year round I can’t hon­estly remem­ber a time when I’ve cramped up dur­ing a run or a race.

In hot ultras I’ve always just drank water and taken salt tabs every 30mins — 1 hour (I’m not a fan of the fla­voured elec­tro­lyte drinks), but this has just been based on gen­er­ic advice rather than some­thing tailored for me.

The res­ults

Turn’s out that I was par­tially right..

I lose 819mg of sodi­um per litre of sweat, so appar­ently I am a “mod­er­ately salty sweat­er”, how­ever, my sweat rate was pretty high.

It turns out that one of the reas­ons that I per­form well in the heat could still well be due to my sweat­ing — I sweat enough to cool me down, but not too much to leave me low in salt.

I was giv­en a tailored hydra­tion plan for a race, and also told what to use in train­ing. This has giv­en me a load of food for thought going for­ward.

What I found super inter­est­ing was that I learnt not only about what to do dur­ing events — which is of course import­ant, but also about the before and after, as well as what to drink dur­ing train­ing. So often the focus is purely on the race, but going for­ward i’m going to put a lot more atten­tion into what I’m con­sum­ing before as well as in my train­ing.


My big takeaways:

1) Con­sider hydra­tion in train­ing

A lot of ath­letes start train­ing mildly dehyd­rated on a reg­u­lar basis and as such can run the risk of start­ing any longer/more intense train­ing ses­sions less than optim­ally hydrated, impact­ing on train­ing per­form­ance which will, in turn, impact race per­form­ance.

2) Pre­load on elec­tro­lytes as well as carbs

By tak­ing a strong elec­tro­lyte (I was recom­men­ded a 1,500mg/l drink, which is ~3x stronger than your typ­ic­al elec­tro­lyte drink) before com­pet­ing in a long race, I was told I can effect­ively “pre­load”.

By doing this I will start races with a big­ger reserve of flu­ids and elec­tro­lytes to draw upon. Boost­ing blood plasma volume before intense exer­cise has been proven to enhance per­form­ance, espe­cially in hot con­di­tions. Hav­ing more blood makes it easi­er for the car­di­ovas­cu­lar sys­tem to meet the com­pet­ing demands of cool­ing you down and deliv­er­ing oxy­gen to your muscles.

What also sur­prised me was that the elec­tro­lyte solu­tion recom­men­ded before was much stronger than what I was recom­men­ded dur­ing.

3) Remem­ber recov­ery

Restor­ing hydra­tion levels is a cru­cial part of the recov­ery pro­cess. Research shows that drinks con­tain­ing sodi­um enable bet­ter rehyd­ra­tion as it allows the body to hold onto more of the flu­id. As such, it just as import­ant to get that 3:1 carbs to pro­tein fuel in straight away post exer­cise, as it is to ensure prop­er hydra­tion.

Hav­ing been through the pro­cess, I would recom­mend Pre­ci­sion Hydra­tion to any­one who is ser­i­ous about their train­ing and per­form­ance. (more details to fol­low if you’ve signed up for the event).

You can take their free online Sweat Test here and, if you want to give their multi-strength elec­tro­lytes a try, use the code ULTRAX15 to get 15% off your first order.



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